The Los Angeles Unified School District is suing the city's housing authority to recover more than $1 million it has spent cleaning lead and arsenic from the soil at David Starr Jordan High School.

The Los Angeles Times reports that, according to the district, the contamination seeped into the soil from a neighboring parcel of land that the Housing Authority of the City of Los Angeles bought in 2008. The district says the school’s arsenic and lead levels now are safe but that the housing authority needs to take responsibility for the work that’s already been done as well as for any future work.

The site, in the Watts neighborhood, was used for heavy industry from the 1930s to the 1970s. Scrap metal was stored there, and furnaces melted scrap iron for use in steel products.

The housing authority “has done nothing to address the hazardous contamination that has migrated” to the school site, despite “the sensitive nature of the school’s occupants and the daily exposure for eight hours a day to the contaminants at issue,” the suit contends.

Housing officials say the school district has not proved that the contamination on campus spread from the industrial site next door, and hasn’t itemized its costs or said how much money it is asking for.